#include <iostream>
// 通过下列 using 声明，我们可以使用标准库中的名字
using std::cin;
using std::cout; using std::endl;

int main()
{
    cout << "Enter two numbers:" << endl;
    int v1, v2;
    cin >> v1 >> v2;
    cout << "The sum of " << v1 << " and " << v2
        << " is " << v1 + v2 << endl;
    return 0;
}